<!DOCTYPE html>
<html class="reftest-wait">
<title>View transitions: setup transition from pagereveal</title>
<link rel="help" href="https://drafts.csswg.org/css-view-transitions-2/">
<link rel="author" href="mailto:bokan@chromium.org">
<link rel="match" href="pagereveal-setup-transition-ref.html">
<script src="/common/reftest-wait.js"></script>
<script>
const params = new URLSearchParams(location.search);
const is_new_page = params.has('new');
if (is_new_page) {
  document.documentElement.classList.add('newPage');

  addEventListener('pagereveal', e => {
    // Setup the view-transition-name from the event. Ensure this is not
    // too late to be discovered to create a shared element animation.
    document.getElementById('target').classList.add('transition');
    requestAnimationFrame(() => requestAnimationFrame(takeScreenshot));
  });
} else {
  onload = () => {
    document.getElementById('target').classList.add('transition');
    requestAnimationFrame(() => requestAnimationFrame(() => {
      location.replace(location.href + '?new');
    }));
  };
}
</script>
<style>
@view-transition {
  navigation: auto;
}
#target {
  width: 100px;
  height: 100px;
  background-color: limegreen;
  position: absolute;
  left: 20px;
  top: 100px;
}
#target.transition {
  view-transition-name: target;
}
.newPage #target {
  left: 300px;
}
/* Hold the transition in the ending location indefinitely. If the transition
 * name was correctly captured in the new page, this will cause the green box
 * to locate at the new position (left: 300px) */
::view-transition-group(target) {
  animation-duration: 300s;
  animation-timing-function: steps(1, jump-start);
}
/* Ensure view-transition snapshots are easily distinguished from live DOM */
:root {
  view-transition-name: unset;
}
::view-transition {
  background-color: thistle;
}
</style>
<div id="target"></div>
</html>
